1. Field of the Invention
The present invention relates generally to cleaning devices similar to vacuum cleaners for removal of foreign particles such as specs of dust, contaminants and alike for in-house or industrial use. More particularly, the method of the present invention describes a cleaning process combining mechanical agitation and pulsed air flow as used for cleaning purposes.
2. Description of the Prior Art
Vacuum cleaning and other methods of removing of dust and other foreign particles are well known in the prior art. Various methods of dust removal were suggested in the past for use in the industrial as well as in-house environment.
Combining the effects of dust agitation from the compressed constant flow air jets with evacuating the air containing dust specs from an enclosed chamber for use as carpet cleaning means in household vacuum cleaners is described in many U.S. patents. Examples of such patents include U.S. Pat. No. 5,647,092 by Miwa; U.S. Pat. No. 5,603,775 by Sjoberg; U.S. Pat. No. 5,454,137 by Reeves; U.S. Pat. No. 4,300,261 by Woodward; and U.S. Pat. No. 4,037,290 by Rose. These patents typically describe various attachments to a commonly used household vacuum cleaner containing a chamber or a shroud placed over a carpet section to be cleaned and having provisions for supplying air jets at a constant flow rate to agitate the fibers of the carpet and to separate the dust particles therefrom. Vacuum hose is used to evacuate the air filled with these suspended dust particles and thus the carpet or a section of the floor is cleaned. Among the limitations of these relatively simple designs, those skilled in the art can point to the limited ability of the constant flow air jets to lift the dust particles and also the inability of these attachments to clean large objects of complex shape, such as a pillow, pieces of clothing, or bed linens due to the limitations of the volume and design of the enclosing chamber. The chamber according to these US patents is typically opened from one end and assumes an available flat surface of the object to be cleaned to form a complete enclosure in combination with that object.
An electrically operated transducer producing agitating waves where this transducer being incorporated in a vacuum cleaner suction head is described in the U.S. Pat. No. 5,400,466 by Alderman. The use of the transducer instead of the air jets is suggested for better and simpler agitation of the dust particles. This design suffers from similar limitation, namely the inability to clean larger objects with complex geometry.
Vacuum cleaners of the prior art are also known to use pulsed air flow as agitation means. Examples of the use of pulsed or reversed direction air flow are contained in U.S. Pat. No. 4,333,205 by Woodward and U.S. Pat. No. 4,174,204 by Chase. In addition to the same limitation of the size and volume of the objects to be cleaned, these designs are quite complex and may have limited reliability.
The use of a large elastic bag for storing and cleaning of large household items made of fabric is known from the U.S. Pat. No. 5,480,030 by Sweeney describing a storage enclosure with provisions for evacuating air. Another example is described in a manual to the vacuum cleaner produced by Rexair, Inc. (Troy, Mich.) describing the use of a large bag ("AEROFRESH BAG") containing pieces of clothing or linen and a manual procedure for the use of an upholstery tool to evacuate the dusty air from the bag. This description does not contained provisions for agitating the item to be cleaned nor suggests repeating of the process at least several times and thus is limited in its efficiency.
Finally, effective dust removal is an important part of the manufacturing process for many industries, especially for the electronics industry. Mechanical vibration coupled with plasma blowing over electronic components is a suggested method of cleaning according to U.S. Pat. No. 5,531,862 by Otsubo and U.S. Pat. No. 5,849,135 by Selwyn. These patents propose the use of a totally enclosed chamber equipped with a mechanical agitator for separating the foreign particles from the object to be cleaned, such as semiconductor components. In addition to a complex nature of these devices, constant plasma flows are suggested which limits the efficiency of the process of cleaning.
Therefore, the need exists for a simple method and apparatus capable of efficient separating and removing the dust particles from an object of complex shape.